Police are investigating an incident involving Anti-Semitic flyers taped to the doors of two Houston-area synagogues, according to the FBI.

Dena Marks is the associate director of the Anti-Defamation League's Southwest division. Marks said a white supremacist group called Vanguard America taped Anti-Semitic flyers on the doors of two synagogues in the area.

She said members of each congregation discovered the flyers on July 16. She is not releasing the synagogue locations for safety reasons and urges the entire Jewish community to be vigilant.

"Be aware that they could be targeted. They need to make sure they have policies and procedures in place for security," Marks said. "I think it's very important for them to tell their staff and their congregants to be aware if they see something, say something. Tell somebody if you instinctively think that something is out of place or wrong."

A spokesman for the Houston branch of the FBI said the agency is aware of the two incidents and that local law enforcement is investigating.

The Houston Police Department confirms it is investigating one incident to determine if it rises to the level of a hate crime.